LARGE1 and proximal spinal muscular atrophy: In the light of the emerging and yet available treatment options for SMA and the remaining need to define biomarkers [28], we performed a proteomic-based discovery study on CSF derived from SMA type 3 patients before and under nusinersen treatment enabling the identification of LARGE1 as a protein increased in SMA patients pre- and post-treatment with nusinersen compared to controls.